Improvement in call-bells



-HENRY A; DIERKES. Improvement in Call Belfls.

Patented March 26, 1872.

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FFIGE HENRY A. DIERKES, OF NEW YORK, N. Y.

IMPROVEMENT IN CALL-BELLS.

Specification forming part of Letters Patent No. 125,029, dated March 26,1872.

SPECIFICATION.

To all whom, 'it m any concern:

Be it known that I, HENRY A. DIERKES, of the city, county, and State of New York, have invented an Improvement in Call-Bells, which I denominate the Duplex Striking-Bell, of which the following is a description My invention has for its object to produce a call-bell of simple construction, reliable in its operation, and of improved tone 5 and it consists in the employment of duplex arms journaled to the standard on one axis, in such relation to a vertical pressure-rod that, when passive, said rod is sustained by and between the two extremities or heads of the arms above their axis; and, when sufficient force is employed to depress the rod, such action causes the hammers to rise and simultaneouslystrike the gong, as hereinafter described.

Figure 1 is an elevation of my improved call-bell, the gong being represented in vertical section to show the striking mechanism. Fig. Z-is a detached view of the pressure-rod and duplex hammers with amodilied form of arms. Fig. 3 is a modification of my device, showing the duplex arms pivoted to the pressure-rod.

As represented in the drawin g, A is the base; B, the standard; and O,the gong. The standard is preferably made bifurcated within and below the gong to admit of hanging the hammer-arms centrally, and its top portion is hollow, to form a receptacle for the pressurerod d, which moves freely within it, and is pro vided with a button or knob, j, at its upper extremity, while its lower end terminates, by preference, in an enlargement, e, which serves to prevent its withdrawal from the standard, and presents a larger surface to act upon the hammer-arms ff. These are journaled side by side, crossing each other, on a pin or other axis, 9, which has its bearings in the standard B, directly below and in vertical line with the pressure-rod. The hammers h h are affixed to the lower extremities of the arms f f, and, when at rest, hang in nearly a vertical position, as represented by dotted lines in Fig. 1, their arms necessarily converging to receive the same axis, and their upper extremities i t forming an acute angle with relation to each other, and giving support to the pressure-rod.

Force suddenly imparted to the pressure-rod causes it to traverse down the incline of the heads or endsi 2', expanding the wedge-shaped opening between them, and swinging the 11ammers simultaneously outward in an arc till they strike the gong. As soon as pressure is with drawn from the knob j the presser-rod is raised by the return of the hammers to their former position. The inclination of the heads timay be increased by forming them beveled, as in Fig. 1, to a greater or less extent, as desired. The duplex hammers, by striking the gong together, produce a fuller and rounder note than that made by a single blow, the effect of the force of two blows acting in opposite directions so modifying the vibrations that they unite and produce a harmonious sound of improved tone, while the same cause acts inechanically to preserve the equilibrium of the gongon its bearing by preventing disadjustment and unequal wear.

Fig. 3 represents an equivalent arrangement, in which the heads of the two-hammerarms are pivoted to the pressure-rod by means of connecting-rods 7c 70. This modification of the construction produces no difi'erenee in the result or principle of operation.

The hammer-arms may be fitted on their axis by slotting one and passing the other through it, or the two may have plane surfaces working side by side.

I claim as my invention As an improved call-bell, the employment of the duplex hammer-rods ff, in combination with the pressure-rod (1, standard B, and gong 1, arranged and operating substantially as shown and described.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

HENRY A. DIEJRKES.

Witnesses:

J. FRASER, GEO. W. MIATT. 

